Portion of a mud flap



FIG. 1 is a perspective view of a portion of a mud flap showing our new design, the broken lines are shown for illustrative purposes only and form no part of the claimed design; and,

FIG. 2 is a rear elevational view thereof.

The front, top, bottom and side views of the design are not visible in their normal intended use. 

The ornamental design for a portion of a mud flap, as shown and described. 